Project Summary Anxiety disorders affect a significant number of individuals and are a significant public health problem. Accurate identification of those who are at risk for the development of anxiety symptoms would allow early intervention and development of prevention strategies. The proposed supplement will collect electrophysiological measures of cognitive control on a large number of participants (N = 291) who have been followed longitudinally since age two. Prior assessments of temperament, social interaction and social anxiety have already been collected on these children, but up until now, have not been assessed for cognitive control. These children have been followed as part of an ongoing grant focused on a separate group of children (N = 291), originally recruited at 4 months of age, for which electrophysiological measures of cognitive control have already been assessed. Collection of these new data will allow us to test the robustness and generalizability of our findings across samples, as well as increase the statistical power of our longitudinal study to identify developmental pathways of risk for social anxiety.